Many computer numerical control (NC) machining systems and industrial robots are capable of changing end effectors to extend the utility provided by a single machining system or robot. For example, most NC mills are equipped with a pneumatic collet within the spindle that can automatically exchange between a variety of tools, e.g., mills, drills, and taps. Similarly, many robotic arms feature an electrical and pneumatic coupling interface between a “master side” and a “tool side” that allows for a variety of tools, e.g., grippers, welders, and deburring tools, to be connected to the end of the arm.
Such systems for exchanging end effectors, however, require extremely precise relative alignment between the locking components of the spindle or robotic arm and the tool. For example, the coupling interface between male and female locking components requires precise axial alignment and precise angular alignment of the electrical contacts and pneumatic ports thereon. Accordingly, tools not currently in use must be stored in precise, known locations to ensure reliable engagement. This necessitates the use of accessories like a tool stand.
Similarly, in NC machining systems, tools are typically stored and rotated for insertion into the collet by a tool change rack. These systems are unsuitable for some robots, e.g., teleoperated robots, as a human operator spends too much time maneuvering the robotic arm to and from the tool stand and attempting to achieve the precise alignment required for mating the robotic arm to the desired end effector.